1. Field of the Invention
The present invention relates to a transporting system provided with a transporting apparatus for transporting a transported object, for example, various substrates and the like for manufacturing semiconductor devices, on a track portion, and a teaching method in the transporting system. Here, the “transported object” means a product, an intermediate product, a part, an article, a work, a partly-finished good, a good or the like, or means a box or container for containing such a product or the like, which has been transported or is to be transported by the apparatus.
2. Description of the Related Art
As this type of transporting system, there is a system having a transporting apparatus of an OHT (Overhead Hoist Transport) type, which travels on the track portion, installed on or near the ceiling. In the system, transfer is made by the transporting device gripping or holding a transported object. In such a transporting system, in order that the transporting apparatus can certainly grip the transported object, teaching is provided about the stop position and the like of the transporting apparatus in performing the transfer.
For example, Japanese Patent Application Laying Open NO. Hei 11-349280 discloses a technology of teaching by detecting a shift amount in the stop position of the transporting apparatus. Moreover, Japanese Patent Application Laying Open NO. 2005-170544 discloses a technology of teaching by detecting a shift amount in the stop position with a recognition mark. Furthermore, Japanese Patent Application Laying Open NO. 2006-69687 discloses a technology of teaching with the correction value of a spatial coordinate position.
However, in some cases, the shift amount and the like of the stop position used in teaching cause errors depending on a positional relationship between the transporting apparatus and the transported object. In particular, the errors are significant when transfer is made by elongating or hoisting a gripping device, which grips the transported object, from the transporting apparatus main body, for example, by the winding and unwinding of a lifting belt or the like, or when a loading device is slid from a traveling device to the side of a track, such as lateral transfer, or in similar cases. Thus, like the aforementioned technologies, if teaching is provided by detecting the shift amount under one condition or in similar cases, there is such a technical problem that accurate teaching is not provided.